The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
A conventional pumping device is attached to a seat such that a seat occupant manually adjusts the height of the seat cushion to match the seat occupant's body shape.
If the seat occupant operates a lever handle installed on the side of the seat cushion clockwise or counterclockwise, the operating force of the lever handle is transmitted to the link mechanism through the seat pumping device to raise or lower the seat cushion in accordance with the operating direction of the lever handle so that the height of the seat cushion can be adjusted.
FIG. 1 is a component diagram showing a conventional seat pumping device. Referring to FIG. 1, a seat pumping device for a vehicle includes: a lever bracket 100 configured to be integrally rotated with a lever handle (not shown) that is operated by a user; a return spring guide 110 in which a return spring 112 providing a restoring force to the lever bracket 100 is accommodated; a housing 120 formed in a drum 122 shape and provided inside a seat cushion (not shown); a clutch mechanism 130 accommodated in the housing 120 and configured to receive a user's rotational operating force through the lever bracket 100 and transmit the same; a brake mechanism 140 configured to cut off torque reversely input and maintain the adjusted height of the seat cushion; and a housing cover 150 coupled to a side of the housing 120 to cover the housing 120.
The return spring guide 110 may be provided with a donut-shaped groove on a side surface to receive the return spring 112.
The clutch mechanism 130 includes: a clutch cam 134 accommodated in a clutch drum 132; a plurality of clutch rollers 136 provided between an outer circumferential surface of the clutch cam 134 and an inner circumferential surface of the clutch drum 132; and a clutch spring 138 configured to elastically support the clutch rollers 136.
On a side surface of the clutch cam 134, a plurality of coupling protrusions 135 are provided spaced apart from each other at a predetermined interval in a circumferential direction. In the middle of a bottom surface 124 of the drum 122 of the housing 120, a through-hole 126 is formed such that the coupling protrusions 135 of the clutch cam 134 are inserted thereinto. The lever bracket 100 includes a coupling drum 104 protruding in an axial direction.
The coupling protrusions 135 of the clutch cam 134 protrude through the through-hole 126 of the housing 120 and are inserted into assembly-holes famed in the bottom surface of the coupling drum 104 of the lever bracket 100 and welded to be integrally coupled with the lever bracket 100.
The lever arm 102, which is provided in the lever bracket 100 and is bent in the axial direction, is elastically supported by the return spring 112 of the return spring guide 110 in the circumferential direction, such that when the lever bracket 100 is rotated in response to the lever handle operation by the user, the return spring 112 is compressed by the lever arm 102 of the lever bracket 100 and provides an elastic restoring force to the lever bracket 100.
We have discovered that since the conventional clutch cam 134 is coupled to the lever bracket 100 via the coupling protrusions 135, and is rotated with respect to the clutch drum 132, when the seat occupant operates the lever handle, the lever bracket 100 and the clutch cam 134 flutter. This lowers the operability of the lever.
The foregoing is intended merely to aid in the understanding of the background of the present disclosure, and is not intended to mean that the present disclosure falls within the purview of the related art that is already known to those skilled in the art.